Explanation:
The direction of waves of contraction in the heart are very important because they represent the cardiac contraction pathway. It begins from sinoatrial node due to spontaneous depolarization (nodal cells) and triggering of action potentials and transmission of the same to the cardiac cells taking part in the conduction pathway in the cardiac muscle fibers.
The blood flows from the right atrium to the right ventricle via the tricuspid valves when the atrium contracts and ventricles expand. Once the ventricles receive its full amount of blood the tricuspid valves shuts to prevent any backflow of blood into the atrium. When the ventricles contract, blood enter the aorta through the aortic valve.
Iron is an important mineral required by the body to produce the ‘heme’ part of the protein hemoglobin present in the red blood cells of the blood. Oxygen binds with hemoglobin and is carried via blood to various parts of the body. Hence intake of recommended dietary allowance of iron is very important since deficiency can lead to various conditions like anemia.
Polycythemia vera is a condition which leads to increased production of red blood cells. this increases the blood volume and thickens the blood and slows down the blood flow and causes blood clots. The slowness of blood flow and formation of blood clots can lead to heart failure and heart attacks respectively.
It is important to keep a high level of physical activity everyday day for many reasons. Keeping a high level of physical activity everyday helps keep you fit. It ensures you burn off any excess calories. It also can prevent future health problems. Exercising everyday creates a better habit.
Answer:
Toys can help with several parts of emotional and social development. For starters, some toys can help children learn to talk and interact, giving them the ability to do so when they get older. They provide lessons in sharing and cooperation. They can help boost the child's self-esteem by being able to do something that he/she couldn't do before. By listening, paying attention and sharing play experiences, helps them explore their feelings and develop self-discipline.
It is considered a third class lever because when you put effort into moving it is more effort on moving than the fulcrum of your arm
~<span>the effort is applied further from the fulcrum than the load</span>
